TOKYO: Japan wants to give planes to the Philippines that Manila could use for patrols in the South China Sea, sources said, a move that would deepen Tokyo’s security ties with the Southeast Asian nation most at odds with Beijing over the disputed waterway.

Four sources with knowledge of the matter told Reuters that Japan was looking to offer three Beechcraft TC-90 King Air planes that could be fitted with basic surface and air surveillance radar.

They said talks within the Japanese government were preliminary and would need to overcome legal hurdles. Japan had yet to formally propose the planes as an alternative to more sophisticated Lockheed Martin P3-C aircraft that Manila wants to track Chinese submarine activity, they added.

Senior Philippine military and defense officials in Manila said they had not heard about the possible donation of the twin-turboprop TC-90 aircraft, which Japan uses to train military pilots.

“The Philippines doesn’t have enough aircraft to conduct regular patrols over the South China Sea,” one of the sources in Japan said, declining to be identified because he was not authorized to talk to the media.

Donating aircraft, even small planes, would represent a military upgrade for the Philippines, which has only a handful of fixed-wing planes it can deploy on maritime patrols.

Tokyo has no claims in the South China Sea, but is worried about Beijing’s construction of seven artificial islands in the waterway’s Spratly archipelago, which will extend Chinese military reach into sea lanes through which much of Japan’s ship-borne trade passes.

Equipping Manila with maritime-capable patrol planes would dovetail with Prime Minister Shinzo Abe’s more muscular security agenda but likely anger China, which has repeatedly accused Japan of interfering in the South China Sea dispute.

A spokesman for Japan’s Ministry of Defense said working level talks had been set up to explore possible cooperation in defense equipment with the Philippines but that there was no “concrete plan” to give Manila the TC-90s.